The objective of this proposal is to synthesize, characterize and test new immunoreagents in form of microspheres of various sizes for the study of cell membranes and the separation of cell subpopulations. During the grant period 8/1/77 through 7/31/80 (Grant No. 1R01 CA20668 MBY), we have synthesized and characterized several types of immunomicrospheres and labeled a variety of human and murine cell membrane receptors. With one particular type and by application of monoclonal antibodies an enhancement of fluorescence by a factor of 100 over the soluble immunofluorescence technique was demonstrated using the mouse IgD5a/IgD5b system. With another type the sensitivity of the immunoephelometric assay was increased by a factor of 1000. Preliminary results with polyacrolein (PA) microsphere opened new possibilities for immunoreagents to improve cell labeling, affinity chromatography and clinical diagnostic techniques. We therefore propose to concentrate our efforts on the development of new and reliable immunoreagents based on PA and extend our studies (1) to improve the stability, size, size distribution, and derivatization procedures; (2) to synthesize magnetic microsphere with improved characteristics; (3) to study the kinetics of radiation grafting of polyacrolein (PA) microspheres to our new as well as to commercially available spheres and investigate the cell labeling and separation possibilities of these new immunoreagents as well as the feasibility of improved immunological techniques; and (4) to collaborate with other scientists involved in basic research of cell membranes as well as in problems related to tumor biology. The collaboration with a) Prof. Noel Warner will focus on cell labeling with monoclonal antibodies; b) Prof. J. Bailey on immobilization of enzymes; and c) Prof. Z. Tokes onthe nature of te bond between PA and adriamycin.